If you read a non-fiction book on any topic, you can probably assume that half of the information in it is just extrapolated from the authors experience.
Even scientific articles are full of inaccurate statements, the only thing you can somewhat trust are the narrow questions answered by the data, which is usually a small effect that may or may not be reproducible...
No, different media are different—or, better said, different institutions are different, and different media can support different institutions.
Nonfiction books and scientific papers generally only have one person, or at best a dozen or so (with rare exceptions like CERN papers), giving attention to their correctness. Email messages and YouTube videos generally only have one. This limits the expertise that can be brought to bear on them. Books can be corrected in later printings, an advantage not enjoyed by the other three. Email messages and YouTube videos are usually displayed together with replies, but usually comments pointing out errors in YouTube videos get drowned in worthless me-too noise.
But popular Wikipedia articles are routinely corrected by hundreds or thousands of people, all of whom must come to a rough consensus on what is true before the paragraph stabilizes.
Consequently, although you can easily find errors in Wikipedia, they are much less common in these other media.
Yes, though by different degrees. I wouldn't take any claim I read on Wikipedia, got from an LLM, saw in a AskHistorians or Hacker News reply, etc., as fact, and I would never use any of those as a source to back up or prove something I was saying.
Newspaper articles? It really depends. I wouldn't take paraphrased quotes or "sources say" as fact.
But as you move to generally more reliable sources, you also have to be aware that they can mislead in different ways, such as constructing the information in a particular way to push a particular narrative, or leaving out inconvenient facts.
If you read a non-fiction book on any topic, you can probably assume that half of the information in it is just extrapolated from the authors experience.
Even scientific articles are full of inaccurate statements, the only thing you can somewhat trust are the narrow questions answered by the data, which is usually a small effect that may or may not be reproducible...